Transmitter.



R. HANSEN. TRANSMITTER. APPLICATION FILED MAY 1, 1907.

Patented Mar. 30, 1909.

wesses.-

muren s'rnrrisr orrion.

RASMUS HANSEN, OF MUSKEGON, MICHIGAN, ASSIGNOR OF ONE-HALF TO INTERSTATE SUPPLY COMPANY, OF SIOUX CITY, IOWA, A CORPORATION OF IOWA.

TRANSMITTER Specication oi Letters Patent.

Patented March 30, 1909.

Application filed May l, 1907.' Serial No. 371,354.

To (LIZ whom it may concern.'

Be it known that I, Yr'nlsMUs HANsnN, a subject of the King of Denmark, and a resident of Muskegon, county of IiIuslegcn, and State oi ltichigan, have invented a new and useful Improvement in '.Iransmitters, of which the following is a specilication.

My invention pertains to details ol construction in telephone transmitters, and has as its object the )rovision of convenient, flexible and reliab e means for adjusting a carbon cell in the bridge, as well as im proved details in assembling the elements o a carbon cell.

As means for adjusting the carbon cell in the bridge, I provide a split bridge of such conformation as to provide elastic sections permitting the required movement of the two sides of the bridge toward each other to clamp the carbon cell, and providing at the same time convenience for mounting insulated terminals for the electrodes of the carbon cell. In the carbon cell I provide a construction which produces the complete cell with a minimum number of structural parts.

In the drawings, Figure 1 shows the plan of my plit bridge with clamping screws in place; *ig 2 shows a. section through the slot of the bridge, showing the carbon cell and terminals in place; and Fig. 3 shows a section of the carbon cell.

In Fig. 1, 1 is a plane piece of metal bored at 10 to receive the carbon cell. From the opening 10 for the carbon cell extend two slots 11 and 12, lending an elasticity to the semi-circular yokes 13 and 141, which together surround the opening 10. Clamping screws 15 and 16 are adapted to draw together the yokes 13 and 14 by drawing together the sides of the slots 11 and 12. I accordingly facilitate the clamping of the carbon cell in the opening 10 by enlarging the ends ofthe slots into the holes 17 and 18 to reduce the cross section of the bridge at the ends of the slots. This forms, as it were, spring hinges upon which the yokes 13 and 14 may swing, the clamping of the carbon cell in the opening 10 thus being very much facilitated and being rendered more accurate on account ofthe ease with which the screws 15 and 16 may be turned into final adjustment; it also permits a greater variation in the outside dimension of the carbon cell,

. inasmuch as with a given strain upon the screws 15 and 16 a greater deliection ol the yokes 15 and 16 may be attained and by the use of a reasonably wide slot at 11 and 12 a great range of adjustment between yoles 13 and 14` may be had, duc to the ease with which the metal of the bridge may be sprung at the section opposite the holes 17 and 18. Further the holes 1 7 and 18 are designed to receive and hold terminals for convenient connection of leading-in wires to the electrodes of the carbon cup, the elasticity of the parts of the bridge being in no wise affected by tlie presence of the terminals in the holes 17 and 13. Holes 19 are drilled for convenience in attaching the bridge to the frame of the transmitter case. As the bridge is ilat, it may be punched from heavy sheet metal and thus may be made at a very low cost.

In mounting the carbon cell in the bridge, a carbon cell 2 having a rigid cup is required. I he terminals or binding posts consist each of a screw 30, an insulating bushing 31, two insulating washers 32-33 and two lock nuts 34. Conductors -from the electrodes of the carbon cell are shown at 35-36, the conductor 35, being upon the side of the bridge having the head of the screw 30, is placed under the head olf the screw thereby extending its circuit through the screw; the conductor 36, being upon the o posite side of the bridge, is placed under tne lock nuts 34 and its circuit thus is carried to the body ot' the screw7 30. Washers 37 and the clamping nuts 38 are provided to clamp the leading-in wires.

The adjustment ol the carbon cell is attained by placing the carbon cell in the open-v ing 10 and attaching its conductors 35-36 to the terminals or binding posts as just described. The bridge is then placed in the transmitter frame and the stud 21 of the carbon cell is attached to the diaphragm of the transmitter. The diaphragm is vibrated to adjust the carbon cell loosely into position in the bridge and the cell then is clamped in that desired position by tighten ing the screws 155-16, thus drawing the yolies 13-14 down closely upon the shell of the carbon cup and locking it permanently.

Turning to Fig. 3, 2 represents the outer shell of the carbon cup. This is internally threaded and drilled centrally to ive ample clearance around the stud 22 o?, the back electrode. The assembly of the carbon cup l. lo) Il is as follows: Within the shell 2 is placed, first,v av closelytting insulating Washer 23 drilled centrally to clear Very closely the stud 22 of the back electrode7 a space ring 24 is screwed doWn upon the insulating Washer 23. This space ring determines the spacing or distance of tlieli'ront electrode from the.

back electrode and takes its name from that function. Its inner cylindrical surface 25 is insulated by a coating of shellac before applyi'ng the'y space ring, o'r may be insulate l by placing strip el paper inside the ring alter it is screwed into: position the doublev line' at 25. illustrates. the insulation of the surface. The back electrode consisting ol a carbon disk 2.6i- Inechanical'ly fastened to thiey brass back plate 2.7,.. which back plate has' the central stud 22.7 then is placed Within the cup and. through the insulating Washer 23. The insulating Waslrer 28 is, placed over' the stud outside' the; cup, the leading-in conductor 36 is: placed upon the' stud 2:2 outside the washer 28, and the lo'cl nut. 29 is screwed down, clamping prlaeethe leading-in conductor 29 and. they back electrode: 2.6.. The insulatino' washer 23 centers the. stud 22 in tl'i'e central opernn'g through the back ol the cu'p. 2 and insulation from the' cu thus is.' providedE by that air space and by t ie washers 23 and 28'. A measured' quantity ofi granular' carbo-n 41 is placed Within the' cup. and theV di'ap'l'nagin 442i is. placed upon the' edge of the s' acev ring 24' and clamped in place by the loc nut Ilreliminarilly the 'liront electrode 4.4, .rnec-h'anieally attached to time: metal su :port 445, which metal` su.y eport l'ras thev centralstud 2l', has been' attaeli'ed tol the diaphragm 4.12 by nuztse 46' and leading-in conductor' 35 has. been attached to(y the stud? 2.1' by the 47.

Having thus described my invention, what I claim as new and.. desire to secure by United States Letters. Patentv is.:

1. In a telephone transmitter, a slotted bridge having' the ends of the slot enlarged,

and binding post terminals for leading-in y Wires mounted in and through. the enlarged ends of the slot, substantially as described.

2. In a tele-phone transmitter, a` split bridge and binding post terminals for the carbon cell electrodes. mounted inV and upon said bridge, said terminals being located in the' ends ot the slot -ofl the bridge., substantially as'y described'.

In' a. telephone transmitter, a split bridge having a slot. se conformed as to re ceive the carbon cell ol the transmitter and tl're anchor' portions oi binding post. terminals for the carbon cell electrodes., subfstantially as described'.

4.. In a telephone transmitter', a. split bridge' reduced cross. section at thea-one est' the ends' of the slotY said. reduced cross section being attained by enlarging thel ends of the slot 5' and' binding osty connector terminals for' the. carbon cel'` electrodes: and for leading-in conductors, said connector' ter'- ininals being anchored by elements: thereof 'passed throughv the' enlarged openingsy at the ends of the; s 'ot oiv the'. bridgeI substantially as described.

Signed: by ine: at. Sioux City, county oi? lVoodbury and Statey ol Iowa, in the presen-ce o'l two Witnesses. l

RASMUS HANSEN.

litnesses.:

MAX. MCGRAW, R.. El. (o'ortns. 

